John Willingham lists one of his awards as Grand Champion for the 1991 American Royal Invitational on the back cover of his book.
Not sure about 1990 though.
22" WSM & Kettle
Former owner: Jambo, Klose BYC, Med. Spicewine, Pitts & Spitts, XL & (2) Med. BGE's, (2) 18" WSM's